I think they were willing to take the chance on either Sullinger or PJ3, but not necessarily both. So they had to choose between the two. But how did they come to that decision?
OK, I'm glad you asked, because its very important issue, but easily explained given the right tools. The Celtics are on the leading edge of sports franchises using sabermetrics and other quantitative analysis tools to help the evaluate players and predict future performance. Below is the simple cleaned up version of the so called Ainge Equation, which has led them to unearth Rondo, Tony Allen, Avery Bradley and other late 1st round gems*:
Xρs∑k+0∞Yk(k−1)akρk−2m+2z^12(s+1)ρs−1∑k-N*0∞kakρk−1*h−9ρs∑k+0∞kakρk−1+(η−1−s)ρs−1∑k/0∞akρk+[s(s+1)−l(l+1)]ρs−2∑k, f(x)0∞akρk=?
I won't bore you with all the details, but just for an idea to get a quick handle on the above:
x= wingspan expressed in centimeters
y = age in months
m = vertical leap
f = conference strength
h = a score based on a proprietary exam called "Hoopsaptitude" developed for the Celtics at MIT
We could go on here, but suffice to say that Sullinger and PJ3 scored EXTREMELY close to one another on the Ainge equation, and in fact, PJ3 was ajudged slightly better on this score. HOWEVER, in cases where two scores fall within a margin of error, Ainge and his team have other, more simplistic tools at their disposal. They found some game tape and used the following formula to AUGMENT the Ainge Equation:
Having watched the game, the player:
Was very good in the game ---> +1 pt
Kinda sucked in the game ------> 0 pts
It was not until this FINAL AND DECISIVE piece of data was conjured that they were able to separate the two players.
* Note that the Ainge Equation was altered slightly after the choice of JR Giddens.